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Q&A for FN America AR-15 Hammer Forged 18 Inch Barrel Rifle Length Gas System 5.56mm NATO 36423 — 3 Questions & 2 Answers

Name FN America AR-15 Hammer Forged 18 Inch Barrel Rifle Length Gas System 5.56mm NATO 36423 (5)
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Q
Dillon Dineen, member, from WI, United States, asked on March 18, 2022

Will this except an A2 front sight post

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A
Answered by Ethan, Gear Expert, from IL, United States, on May 02, 2022

Yes, the FN America AR-15 Hammer Forged 18 Inch Barrel will accept a fixed front sight as long as it is compatible with a 0.750" gas journal. You would also need a rifle length gas tube.

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Q
Kurt, guest, from TX, United States, asked on June 11, 2020

Hi, I need to know if this barrel accepts pinned gas blocks or will it only accept a slip on. I know it's .750 diameter, not sure on the rest. Thanks.

A
Answered by Jon4324, guest, from TN, United States, on March 05, 2021

You would have to drill the barrel if you wanted a pinned gas block. Normally the block and barrel are drilled together for perfect alignment. You can also just simple the barrel and use a low profile gas block which I would recommend unless you really like having the fixed sight block.

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Eagle, guest, from TX, United States, asked on August 07, 2025

Hello is this a 1-7 twist barrel and also chrome lined?. Ease and thank you

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